Pneumatic take-down and automatic press-off of seamless hose and socks from single-cylinder machines was a comparatively easier problem to overcome than the automatic separation of half-hose on double-cylinder machines which was achieved by Bentley in 1967. Pressing-off occurs at the point where the draw-thread would normally be introduced when the needles are engaged with the bottom cylinder sliders. The first few needles are raised to non-knit height in advance of the loop-forming position of the main feed so that the yarn from the previous article passes across them under tension and is severed as the sinkers move radially inwards and kink it with their throats.
At the main feed, the yarn for the new article is taken into every needle hook in the bottom cylinder. To ensure that all hooks are open, the needles have extended latches that are opened by the extended pointed ends of the sliders, which receive a rocking motion from cams at the transfer position. During this revolution, alternate needles are transferred to the top cylinder where they knit one course whilst the needles in the bottom cylinder remain in the non-knit track. For the next course, the rib needles enter the welt track and the plain needles are cleared to knit at the main feed for the commencement of the welt.
The Bentley-Solis arrangement [5,6] employs vacuum suction complemented by a mechanical system to withdraw the separated article from the knitting zone. For reversed take-up, an inner plastic delivery tube then sucks the article upwards through the top cylinder where it drops onto a hinged exit door that automatically opens to allow it to fall into a collection container. The revolving take-down arrangement consists of two independently-operated sleeves positioned, one within the other, at the lower end of the top cylinder, with the inner sleeve protruding below the outer. The fabric is alternately held and pushed downwards by the sleeves, which are lifted and dropped once per revolution by cam action. The inner plastic delivery tube is slightly shorter than the inner sleeve so that it can suck the article upwards and away from the sleeves.
Was this article helpful?